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1982 300 TD
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Discussion Starter #1
My 82'300TDT is running hotter than it used to. I don't think the fan is working. Is there a way to test the electric fan motor in front of the radiators by splicing in a wire to the fans +red wire and connecting the spliced in wire to some place under the hood? Maybe the fuse it runs on? I touched it (with the ignition on) to the battery positive+ and got a violent spark. I tried it on the fuse box (on the wrong fuse)not the one for the fan,etc. and blew that fuse. I would like to wire it to operate manual by putting a electric on/off switch under the dash area, but I don't know even if the fan motor works. Thank you for any advice concerning this question.
 

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84 230CE & 84 300DT
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The fan is thermostatically run. Usually it kicks on at about 100 degrees C. You can certa...

The fan is thermostatically run. Usually it kicks on at about 100 degrees C. You can certainly here it run, but it only runs with the ignition on.
 

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1982 300 TD
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Thank you for your info on hearing the fan, which I never have. Is there a way to bypass...

Thank you for your info on hearing the fan, which I never have. Is there a way to bypass the thermal switch and wire it to direct somehow just to test if the fan motor works? Then I could know if it were the thermal switch. Thank you.
 

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84 230CE & 84 300DT
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You probably could, but do not run a jumper wire to your battery. That can cause you explo...

You probably could, but do not run a jumper wire to your battery. That can cause you explosion that could ruin your day for sure.
Disconnect both wires from the fan. Use a test light to locate a hot lead and connect your jumper wire to that. Make sure also that you are able to supply a ground wire for the other wire as well.
 

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Checking Auxiliary Fan

lieutviai,

I don't have an aux. fan (car didn't have one when I bought it), but I tried checking the wire that has a plug, which connects to the aux. fan's plug, for voltage with a voltmeter, with car on, with A/C on, etc. and it showed zero volts. So, I should get voltage only when the temperature is above 100 degrees celsius? I'm going to be getting a fan soon, and just wanted to make sure everything is in order for it to work.
 

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84 230CE & 84 300DT
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WSAD,
Did your car ever have aux fan? It probably did since you have a plug for it. Trace...


WSAD,
Did your car ever have aux fan? It probably did since you have a plug for it. Trace the wires that run from the plug back to the sensor and check the wires that go into the sensor to check for juice. Check it with the ignition in the on position. That should tell you if it will work or not. It's only my estimate on the 100C temperature if the fan goes on. It may be more or less. I don't remember if there is a mark on the sensor to indicate at what temperature it begins to work. If there is any doubt about the sensor, try removing it , attach a test meter to it and put in a pot of water and bring it to boiling with a thermometer in it. You can see at what temperature it begins to work if at all.
 

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I think so

I'm pretty sure it did, but I think it was involved in an accident, and a replacement was never put back on. I'll have to check out those wires. Thanks.
 
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